////////////////////////////////////////////////////////////////////////////////
/// @brief class used for timing purposes
///
/// @file
///
/// DISCLAIMER
///
/// Copyright 2004-2012 triagens GmbH, Cologne, Germany
///
/// Licensed under the Apache License, Version 2.0 (the "License");
/// you may not use this file except in compliance with the License.
/// You may obtain a copy of the License at
///
///     http://www.apache.org/licenses/LICENSE-2.0
///
/// Unless required by applicable law or agreed to in writing, software
/// distributed under the License is distributed on an "AS IS" BASIS,
/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
/// See the License for the specific language governing permissions and
/// limitations under the License.
///
/// Copyright holder is triAGENS GmbH, Cologne, Germany
///
/// @author Dr. Frank Celler
/// @author Copyright 2005-2012, triAGENS GmbH, Cologne, Germany
////////////////////////////////////////////////////////////////////////////////

#ifndef TRIAGENS_BASICS_TIMING_H
#define TRIAGENS_BASICS_TIMING_H 1

#include "Basics/Common.h"

namespace triagens {
  namespace basics {

////////////////////////////////////////////////////////////////////////////////
/// @ingroup Logging
/// @brief used for timing tasks
///
/// In order to get timings for a task, you must create an instance of Timing
/// at the beginning of the task and use passed to get the microseconds since
/// the beginning. You can use resetPassed to get the microseconds and reset
/// the timer to a new beginning.
////////////////////////////////////////////////////////////////////////////////

    class Timing {
      public:

////////////////////////////////////////////////////////////////////////////////
/// @brief timing types
////////////////////////////////////////////////////////////////////////////////

        enum TimingType {
          TI_DEFAULT = 0,
          TI_WALLCLOCK = 1,
          TI_RUSAGE_USER = 2,
          TI_RUSAGE_SYSTEM = 3,
          TI_RUSAGE_BOTH = 4,
          TI_UNKNOWN
        };

      public:

////////////////////////////////////////////////////////////////////////////////
/// @brief constructs a new instance
////////////////////////////////////////////////////////////////////////////////

        explicit
        Timing (TimingType type = TI_DEFAULT);

////////////////////////////////////////////////////////////////////////////////
/// @brief copy constructor
////////////////////////////////////////////////////////////////////////////////

        Timing (const Timing& copy);

////////////////////////////////////////////////////////////////////////////////
/// @brief assignment
////////////////////////////////////////////////////////////////////////////////

        Timing& operator= (const Timing& copy);

////////////////////////////////////////////////////////////////////////////////
/// @brief destructor
////////////////////////////////////////////////////////////////////////////////

        ~Timing ();

      public:

////////////////////////////////////////////////////////////////////////////////
/// @brief microseconds passed
///
/// Returns the number of microseconds passed since creation or last reset.
////////////////////////////////////////////////////////////////////////////////

        uint64_t time ();

////////////////////////////////////////////////////////////////////////////////
/// @brief microseconds passed and reset
///
/// Returns the number of microseconds passed since creation or last reset
/// and resets the timer.
////////////////////////////////////////////////////////////////////////////////

        uint64_t resetTime ();

      private:
        struct TimingImpl* impl;
    };
  }
}

#endif
